A study of admission, treatment, and discharge of patients at McLean Hospital, Hartford Retreat, Worcester State Hospital and the Institute of the Pennsylvania Hospital from their establishment through 1860. This study includes analysis of the incidence and prevalence of insanity in 1854-55 as established by a survey conducted by Edward Jarvis for the Massachustts Census (1855); this includes study of the determinants of institutionalization and discharge. Research is conducted in resources noted above and in manuscript hospital records including patients' case records, and the manuscripts and published documents of institutions and superintending physicians. The findings are partly based on statistical analyses using multiple classification techniques to examine demographic, somatic and behavioral characteristics associated with commitment. Patients records are coded and analyzed separately from general register materials, and all data are deposited in OSIRIS Format at the Inter-University Consortium of the University of Michigan. General registers of cases chronologically arranged will be deposited with the library holdings of the separate institutions to facilitate further research. Preliminary papers on cause of commitment and on the institutional population over age 60 have been completed for conference discussion and are being prepared for publication. Also in preparation are papers on methods of collecting data from manuscript clinical records and on recidivism rates of patients in the institutions studied.